windhausen



(No Model.) 3 Sheets-Sheet 1.

' P. WINDHAUSEN.

'VAGUUM PUMP. No. Z47,456.- v Patented Sept. 20.1881.

Fig.2.

N. PETERS. Phmu-Lithagmpht. Wuhinglon. n.c.

1 (No Model.)

- 3 Sheets-Sheet 2. P. WINDHAUSEN.

VACUUM PUMP. No. 247,456. Patented Sept-20, 1881.

Fig.5.

(No Model.) 3 Sheets-Sheet 3. P. WINDHAUSEN;

VACUUM PUMP.

Patentd Sept. 20, 1881.

N. FUCHS. Nomi-19hr, Walhinflon. l C.

UNITED STATES PATENT OFFICE.

FRANZ WINDHAUSEN, OF BERLIN, PRUSSIA, GERMANY, ASSIGNOR TO FRANZ HERMANN EGELLS, OF SAME PLACE.

VACUUM-PUMP.

SPECIFICATION forming part of Letters Patent No. 247,456, dated September 20, 1 881,

Application filed June 9, 1880. (No model.)

To all whom. it may concern Be it known that I, FRANZ WINDHAUSEN, of Berlin, Prussia, Germany, have in vented a new and useful Improvement in Vacuum-Pumps, of

5 which the following is a specification.

My improvement relates to the construction of a compound pump for the purpose of creating a vacuum by exhausting the air and vapor from a suitable receiver or absorber of an icemachine, the air and vapor being then compressed to the tension of the atmosphere and discharged into the surrounding air.

My invention consists, first, in combining with a pipe connected with a receiver in which it is desired to create a vacuum a large pump adapted to exhaust air and vapor through said pipe, the admission of the air and vapor to the pump being regulated by valves, which are opened by suitable means when the air has expanded in the cylinder sufficiently, valves regulating discharge, and a small pump adapted to draw the combined air and vapor from the large pump, recompress it, and discharge itinto the atmosphere, as hereinafter described.

2 5 My invention consists, further, in combining with said apparatus a condenser having an. injection-pipe adapted to conduct water for liquefying the vapors sucked from the receiver, as hereinafter described.

My invention consists, further, in combining with the suction-valves of thelarge pump means for opening the valves after the piston has traveled acertain distance, consisting of levers connecting with a cam or eccentric on the main 7 3 5 shaft and springs adapted to close the valves,

as hereinafter described.

My invention consists, further, in combining with the suction and discharge valves of the large pump a relief-valve consisting of a suit- 40 able box divided by a horizontal'partition into two chambers communicating by channels with the discharge and suction valves and a liftingvalve pressed down by a suitable spring, as hereinafter described.

4 5 My invention consists, further, in combining with a hollow piston a metallic packing-ring, a flexible and air-tight ring having in-turned edges, a metallic ring inserted between said edges, and a pressure-regulator, as hereinafter described.

and F the condenser.

The invention is represented on the annexed sheets of drawings, in which Figure l is a side elevation of the pump. Fig. 2 is a plan. Fig.

3 is a section on a larger scale, according to the line 00 m y y of Fig. 1, but without the mechan- 5 ism by which the pistons are worked. Figs. 3 3 4, and 5 show details, while Fig. 6 represents a modified arrangement of the pump.

D is the large pump, D the small pump,

The pump D, which is, by preference, double-acting, is in communication, by means of the suction-pipe c, with the receptacle in which the vacuum is to be produced, and by the discharge-pipe c with the condenser F. The pipe 0' is consequently the suction-pipe of the small pump D which discharges by the pipe 0 its contents of air and the water aspired from the condenser.

n n are the suction-valves, and n n the discharge-valves, of the large pump. Of the lat- 7o ter valves, the upper one is pressed against its seat by its weight, the lower one by a spring, and both valves open automatically as soon as the pressure in the cylinder exceeds the pressure in the discharge-pipe. The suction-valves 5 are operated by 'a suitable mechanism in such a manner that they open alternately after the piston has traveled from its end position over a certain part of its course. This mechanism consists, by preference, of the levers o 0, connected by suitable rods with the eccentric 0 (or a cam-disk,) keyed on the main shaft q, or

otherwise rotated at the required speed. The levers 0', when pressed with their ends against the valve-stems, will not open the'valves until 8 5 their tension becomes greater than the counterpressure acting on the valves from the inside of the cylinder. For the purpose of closing the valves they are provided with springs o 0, which draw them against their seats, and the 0 closing of either valve takes place when the piston is at .or near the end of its stroke, and as soon as the valve is relieved from the pressure of its lever o. A similar operation of the valves may, however, also be caused by other means, the object to be attained being not to open either suction-valve until the air remaining in the cylinder at the end of any stroke has expanded again to a certain degree, (and, by preference, to about the pressure in the suc- 10o Lil tion-pipe,) so as to cause a complete and secure closure of the discharge-valve. The opening of the suction-valve is thereby at the same time facilitated.

The piston 11 is operated from a crank on the shaft (1 by means of a connecting-rod, of the beam 19 and of the rod p the latter being jointed to the piston inside of the trunk p. This mechanism may, however, be varied, as it does not form any part of the invention.

For the efiiciency of the pump it is of the utmost importance that the piston p be provided with a perfectly air-tight packing. The one which I use by preference is represented in Fig. 3, and in detail in Fig: 3. It consists of a metallic packing-rin g, p, which is pressed by its own elasticity against the wall of the cylinder. Behind this ring is placed a ring, if, of india-rubber or other air-tight and sufficiently-flexiblematerial,whoseedgesareturned inward so as overlap a metallic ring, 12 inserted between them. The ring 19 is of such a thickness that the edges of the ring p will be pressed air-tight between the body and the cover of the piston and the said ring 12 when all parts of the piston are screwed together. The space between the india-rubber ring 12 and the ring 1) communicates by holes with the interior of the hollow piston, in which an air-pressure is maintained somewhat above the maximum pressure in the cylinder. The difference between these pressures serves to press the flexible ring 12 against the packingring 12 and to increase the pressure of the latter against the wall of the cylinder.

The requisite air-pressure within the piston is kept up by a pressure-regulator, It, Figs. 3 and 3 connected with the piston by the pipe r. The spring T with which the valve of this regulatoris provided, is adjusted in such amanner that the valve opens by the atmospheric pressure and allows air to enter the piston whenever the pressure within the samebecomes too low. Considering that the air which the piston 11 expels at the commencement of its working has a tension considerably above the mean pressure of the air discharged from the large cylinder, the piston would at first have to overcome too. great a resistance if an arrangementwere not provided for by which this pressureisprevented from exceeding a certain limit. This arrangement consists in a return-valve inserted between the discharge-pipe and the suction-pipe, or between the boxes of the discharge-valve and the suction-valve, the said return-valve allowing a part of the air discharged to return into the suction-pipe as long as the maximum pressure in the pump is higher than desired. This valve may be constructed as is represented by Figs. 1 and 4. The box w, which incloscs the valve, is divided by a horizontal partition, s, into two chambers, s and 8 the former communicating by the channel '0 Fig. 5, with the box of the suction-valve a, the latter by the channel 0 with the box of the discharge-valve n If the said valve 8 is pressed by means of its spring 8 in such a manner against its seat on the partitionwall 8 that it opens at a difi'erencc of pressure on its two sides of, for instance, one-tenth atmosphere, air will or may at every stroke be returned from the discharge-valve box to the suction-valve box until the maximum pressure in the pump is reduced toone-tenth atmosphere. When this point is attained the valve does not open any more, and for providing against any subsequent passage of air it may then be pressed tightly against its seat by means of the screw 8".

The air discharged from the large cylinder at a pressure varying, under regular working conditions, between one-fortieth and one-tenth atmosphere is aspired by the pump D compressed by the same to atmospheric pressure, and thereupon discharged through pipe 0 This pump is shown in the drawings as being single-acting; but it may be made double-acting, if preferred. Its piston is worked from the beam 12 by the connecting-rod 17 or in other suitable manner. The condenser which, according to Fig. 3, surrounds the pump D is of importance when the pump is used for the extraction of vapor resulting from a process of evaporation or desiccation. This vapor is condensed by water introduced in a fine spray, and at as low a temperature as possible, by the injection- )ipe t, whereupon the water collecting in the condenser is aspired and discharged, together with the air, by the pump D In Fig. 6 a compound pump is represented, which is not provided with a condenser, and whose arrangement differs in some respects from the one described in the foregoing; but these differences need no explanation, as they will easily be understood from the drawings. Although this pump has no condenser, it may, nevertheless, also be used for extracting vapors, which, in such case, are discharged in gaseous form; but this mode of proceeding does not present the advantages as the extraction with the aid of a condenser. For the purpose, however, of causing at least a partial condensation of vapors the cylinder of the small pump may be provided with two pipes, t t, serving for the injection of a certain quantity of water into the pump itself.

By means of the described compound pump a rarefaction of air and vapor as low as one six-hundredth of an atmosphere and even less, may be attained, which is a degree far beyond the rarefaction that can be arrived at by common air-pumps used for industrial purposes. The improved pump may, with advantage, be used for the evaporation and concentration of liquids; moreover, for the desiccation of meat, vegetables, and other organic substances, as also of dead human and animal bodies,when such are to be preserved from putrefaction, and for all other industrial processes requiring to be carried out in a vacuum.

I am aware that it is old to use two or more pumps for the purpose of storing air under IIS pressure, and do not claim such pumps broadly.

I am also aware that it is old to use reliefvalves, by which a portion of a liquid passing through an apparatus can be returned from whence it came, and do not claim such reliefvalves, broadly.

I claim as my inventiou 1. In a pump adapted to create a vacuum in a receptacle and compress the air withdrawn therefrom to the tension of the atmosphere, the combination, with a pipe connected with a receptacle in which it is desired to produce a vacuum, of a large pump, D, valves n and n mechanism 0, for closing the suction-valve 12 and the small pump D for recompressin g the air and delivering it to the atmosphere, as set torth.

2. A condenser, F, provided with a waterpipe, t, adapted to reduce the vapors sucked from the receptacle, in combination with a small pump, D a large pump, D, suctionpipes c and a, suction and discharge Valves n and n valve-closing mechanism 0, and a suitable discharge-pipe, as set forth.

3. The combination, with the suction-valves of the large pump, of the closing-springs o 0,

opening-levers o 0, cam disk or eccentric o, and main shaft q, the whole arranged and adapted to operate as set forth.

4. The combination,with the discharge and suction valves'n n of the large pump, of the relief-valve, consisting of box w, having horizontal partition 8, forming chambers s and .9 channels a and v communicating with the suction and discharge valves, respectively, liftvalve 8, and spring 8 as set forth.

5. In combination with the hollow piston 11, the metallic packing-tin g1), the flexible and airtight ring 12 and the rin g p, the space between the ringsp and p communicating with the interior space of the'piston, and, by means of a pressure-regulator, R, with the outer air, as hereinbefore described, and for the purpose stated. a

In testimony whereof I have signed myname to this specification in the presence of two subscribing witnesses.

FRANZ WINDHAUSEN.

Witnesses:

BERTHOLD R01, BANCROFT O. DAVIS. 

